text: #ifndef CBM_WIDGETS_SCREEN_HPP
  #define CBM_WIDGETS_SCREEN_HPP
  
  #include <set>
  
  class Window;
  
  class Screen {
      public:
  	Screen();
  	~Screen();
  	
  	unsigned getWidth() const;
  	unsigned getHeight() const;
  
  	void update();
  
      private:
  	Screen(const Screen&);
  	void operator=(const Screen&);
  
  	void addChild(Window* window);
  	void removeChild(Window* window);
  	
  	void* win_;
  	friend class Window;
  	typedef std::set<Window*> Children;
  	Children children_;
  };
  
  #endif
  